5. The Infinity Gems... Aren't Actually The Infinity Gems
So, something we learned from the mid-credits scene with Benicio del Toro's Collector character is that the Tesseract and the Aether are actually two of the six items that are considered to be the Marvel Cinematic Universe's interpretation of the Infinity Gems. This didn't exactly prove anyone wrong (it's not as if anyone outright said "the Tesseract isn't an Infinity Gem!"), because no one would have ever thought to bother arguing such an abstract point prior to this movie, but it did disprove a very basic assumption that the Infinity Gems would be the same as they were in the comics. In the comics, the Infinity Gems are simply named after the particular aspect of the universe that they grant control over (space, time, mind, reality, power and soul) and the Tesseract (or Cosmic Cube) is a completely separate object which is essentially a not-quite-so-powerful, scientific version of the Infinity Gauntlet (granting the ability to warp reality on a massive scale). To describe the scene with the Collector in a little more detail, he meets with Sif and Volstagg as the Asgardians have decided that it would be "unwise" to keep the Aether so close to "another Infinity Stone" - that being the Tesseract - and, when he gets his hands on the Aether he says "one down, five to go", meaning he wants all six for himself (of course, so does Thanos, but that's another story...). Oh yeah, the Marvel Cinematic Universe also refers to the gems as "Infinity Stones". Just so you know.